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The Aral Sea(咸海) is in central Asia (亚洲中部). It is a salty lake. It is the world's fourth-biggest lake(第四大湖). Today, over 90% of the sea is dry. why does the Aral Sea shrink (消失)? First, the Aral Sea only gets water from two rivers, Amu Darya(阿姆河) and Syr Darya(锡尔河). Cotton farmers use much water from the two rivers. The sea can't get enough water. Second, more(更多的) people live near the Aral Sea than before. They take water from it. The Aral Sea loses more water. It becomes small and very salty. Many fish die! Five countries in central Asia are trying to save the Aral Sea. But it's hard. Don't waste(浪费) water, please. It's useful for us.